Building Logs

Dont call in the pro’s

Posted by Paul

Not a lot to report unfortunately. At least not in this post.

The going got extremely slow on the outboard tracks for a couple of reasons. Firstly, for the last week and a half I have had the flu which left me lethargic and tired, because unlike in the past, I still have to work to keep paying the shed rent. The other reason work has been slow has been the issues I have found with the outboard trucks and bearings. Let me refresh you on this long saga.

A couple of years ago I got a rough quote to weld me up 2 aluminium transom trucks (I call them trucks because onto them are bolted cars that run on sail tracks, so as not to confuse the entire bracket with the sail track cars, I call them trucks) and it was ridiculously expensive. So we made up solid glass trucks out of fibreglass (both uni and double bias) and resin on a mould of the transom required. In the middle is a 25mm ply pad embedded in about 6mm of glass each side so that when the 2 sides come together at the corners and turn 90 degrees the thickness of the sides is 12mm solid glass. The sides turn again outward to form 2 flanges about 50mm wide and 12mm thick, to which the sail track cars are bolted to. The tracks get bolted to the bulkhead inside the outboard well and the entire contraption runs up and down on the tracks, not unlike this pic following, taken off the internet of an Arbor Cat for sale in Queensland, in fact they are using the exact same tracks that I have. (I hope they dont mind me using the pic to demonstrate what I had intended)

outboard mechanism

When we mounted it all in last year using the borrowed Etec 25 on one side and Terry’s 20hp Honda’s on the other the aluminium cars on the aluminium tracks bound up and would jam. So it was decided that the issue was the alli to alli. So I paid a local company to make me plastic cars to run on the alli tracks. After waiting about 3 times as long as they promised (6 weeks instead of 2) we tried the new plastic cars bolted in to the truck and onto the tracks with the borrowed etec and these also bound up. In the meantime I had the rudder bearings made by the same company and it took about 8 times the promised 2 weeks (I expected 6 from my previous experience but was rather annoyed when it turned out to be closer to 20, about 4 months in all) before I finally had them, so I kind of new what to expect when I went to them for a third time to make what I hoped would be the final iteration of the outboard raising and lowering mechanism.

Utilising the trucks I already have I commissioned the nimrods at the the plastic company  to make me a set of bearings that would wrap around the ends of the flanges and fit snugly inside an aluminium C channel on each side. I specified a C channel bearing to inside the aluminium channel and fit over the fibreglass end flanges. I left them a piece of C channel and the 2 trucks so that they could machine the bearings to suit the channel and the flanges that, being hand made might not all be uniform in thickness. They had these parts for the better part of 7 months, I delivered them in early November last year, and got them back in May. The problems I am currently having, in retrospect are probably related to the delays in getting my job done. On the last 2 times I visited them to collect the work only to be informed they still had not done them I warned them my patience was coming to an end and if not done I would have to take the parts back and have someone else do them. As a result I am sure they were rushed, were not what I had originally requested them to do and as it turns out, were completely botched as the current range of problems attest to.

Because the C channel has threaded bolt holes and the bolts go through the bulkhead from the inside out I cannot be on both sides of the bulkhead at the same time, so this is one of those jobs that just has to have a second person helping. Enter the experienced  hand and mind of Terry to help. First we mounted one of the channels square and plumb. We marked the holes and drilled them (the first time we used the sail track as a guide but after that we just positioned the channel and marked the first hole, drilled it and bolted the channel on then ran a spirit level along it and marked the rest of them with a screw through the bolt hole. I say first time, because as you will read, we mounted and re-mounted these C channels 3 times until we got it right! Once the holes were drilled one of us would go inside the boat and tighten the bolts through into the C channel. With the first C channels mounted square and plumb the second side was a matter of using the truck as a spacer, clamping to the mounted C channel on one side to hold it firmly in place while we positioned the other C channel against the other side of the truck and marked the top and bottom bolt holes (we moved the truck to top or bottom whilst marking its respective bolts). This is where the fun and games began.

So we have carefully mounted the C channels in the starboard hull and then we place the truck into the C channel tracks and the damn thing wont budge. Its jammed. We tap it down and suddenly its too loose, and by too loose I mean 5mm too loose. Then it binds again, too tight. WTF is going on here. The channels are dead straight. The bolts are not loose so the channel is not moving (just on that, I bought stainless steel bolts with pan heads and star sockets because the heads would be visible in the laundry and possibly the bedroom until the liners eventually go on the walls and these looked better than normal hex head bolts. Big mistake. In doing these bolts up too tight to ensure the C channel wasnt moving and was the cause of the binding we couldnt get one of them back out and the star socket stripped and a simple 20 second job turned into 20 minutes as we tried everything to get the thing back out. I tried cutting a slot into the head with a cutting blade on the angle grinder but the slot was too wide and the screwdriver would just slip. Eventually we ground down the sides and used multigrips).

We measured the bearings and they were all over the place in terms of width apart. The 2 trucks did not match, and whilst this is not an issue, and I did not specify that they should, the actual fibreglass parts do, so you would think the bearings would too. But this was not the problem anyway. They were only a millimetre or 2 out, the gaps we found top to bottom were 5mm. What did we do wrong? We seemed to have the full face of the bearing against the C channel on each side but perhaps we did not and this was it. So I refilled the holes with filler and we had to come back the next day to try this all again. In the meantime I was already unhappy with the job the plastic company did, the delays and now to find the bearing surfaces not exactly the same size. Even though the 1mm difference was not the problem, when you pay people for services that require exact measures you expect to receive exact measures.

So next day, fresh drill holes, and this time we not only used the truck as a spacer method, we also measured the truck and the space and they matched exactly. The truck bearing surfaces are 1mm wider at the bottom than the top due to one of the 4 spacers protruding 1mm (so not both of the surfaces on the side that was out was actually out, so only half the bearing surface was proud, but it was enough make the spacing wider at the bottom than the top) and we thought this might work in our favor. It would mean that as the truck moved down it would get tighter, which suits the situation. The truck will be under torque twist load from the outboard prop thrust when down but only under gravitational load when raised. So being a little looser top to bottom is a good thing. I doubt the plactic guys engineered this in but you never know.

All measures lined up so we drilled again. Mounted the second C channel, slid the truck in in anticipation and the damn thing bound again. At this point my limited knowledge is exhausted for ideas on what the heck is going on. Fortunately for me I had Terry’s big brain on hand. So we took another good look at the Jerry built bearing surfaces. The edge of a T square told the sorry tale. Probably THE most important facet of the bearings was out. You just assume when you pay people to build things for you….lesson; never assume paid professionals either care more or are better at building something than you are. Here is the pictorial evidence:

transom bearing flush gap transom bearing gap when level held flush to other side

When a straight edge is run over the bearings one side to the other they are not flush to each other. In the first pic you see the angle of the bearing to the highest point. The view is the same on the other side of the truck on the other bearing, only mirrored. It doesnt look like much, less than half a millimetre over the width of the bearing surface. But take a look at the extent of the issue when one side of the straight edge is held flush to one bearing. Across the width of the truck the difference at the other bearing is about 4mm. Enough to bind them in the C channels. It just staggers me that any company could produce such work, when they knew exactly what the job was for and how it would work if done properly. And yet they are so busy, they could not do my job for more than half a year. Therein lies some of the reason I think, my job just wasnt important enough to them.

Terry knew exactly what the problem was or more precisely how to fix it. The trucks had what Terry called “spring” in them. That spring was causing the sides to splay out and the faces of the front bearing surfaces out of alignment as a result. We placed a clamp across the trucks (yes both had exactly the same issue, one just a little less than the other but both enough that the system would never work unless we fixed them) and pulled the sides in towards each other and just a few turns of the clamp later and the straight edge of the T square told the tale. Dead flush. So the permanent solution to a problem that has been there all along and probably the reason the original sail track and cars did not work was $20 worth of threaded 316 stainless rod and washers and nuts. I applied 2 tie rods to each truck (one top one bottom) and this pulled them into line.

transom truck bearing faces leveled transom bearing gap gone

Next day (yep each time these hurdles pop up they usually cost you the rest of the day, that and I start work at 3pm most days) we go back to the C channels and the system finally works. Not brilliantly but no binding and releasing. We (or more accurately Terry decides its just the few faces here and there and the not well rounded edges now causing the problems and he will take the trucks home and machine them perfectly to finish them himself) but the C channels can finally be fixed in place. Fixed in place means the existing holes that are now in the wrong place refilled, new holes drilled, then over drilled, then refilled then redrilled. And one of the C channels when re positioned with the new square faces pulled in by the tie rods, had moved 5mm. Amazing. So in all, I think I drilled the bolt holes about 5 times, x 12 bolts per channel x 4 channels = 240 holes drilled, about 130 of them filled again! One time for the original sail tracks, then they were back filled when we moved to the C channels. Then we pulled the sides of the trucks in with the tie rods meaning the holes moved 5mm. We kept one side where it was and only moved the other side, even though the trucks are now 5mm to one side of centre, fortunately the transoms are about 30mm wider than an outboard mounting bracket so the outboard can just be moved the 5mm to make it up, then once we finally had everything where it should be, every hole was then over drilled with a 12mm drill bit (M6 bolts so 3 mm of fill all around the bolt to ensure watertight bulkheads) and redrilled with the 1/4 bit (slightly oversize for an M6 bolt) to finish. Phew. Backfilling gets tiresome fast. Essential pain in the butt.

transom truck in its tracks 2 transom truck in its tracks

Terry machined the faces of the bearings (planed and sanded and rounding the edges and corners) and slotted the fixing bolt holes so the bearings could be more easily adjusted should the need arise. All now square, flush, plumb and true. And the system all works well as it should have all along. Its not a complicated idea. It should have worked with the sail tracks and cars, but the faces of  the fibreglass flanges were out all along. I didnt have the engineers mind to measure that and just assumed that the system was causing too much friction to work and easily moved on to the next most logical solution, in the first instance changing the cars and then to the current idea of channels instead of tracks. Had I checked the trucks and found the issue I would probably still have the tracks and original cars and would have spent just the $20 to fix the problem and not $600 = $200 for the plastic cars, then $100 for the aluminium tracks and $300 for the new bearings. Had I built the trucks myself and not paid a “professional” 2 things may have happened, first I would have made them right in the first place or failing that (giving the builder the benefit of the doubt, that the glass sets and then springs) would have known what to check for.

A pro built my trucks and to be fair to him, they may have come off the mould true, but at some point later a spring appeared in both to splay the car or bearing surface away from plumb. That spring may have also happened as a result of the weight of an outboard on them, but after all that is what they are designed to carry. (any further spring that might develop although unlikely, will now be controlled by the tie rods). And then another pro built the bearings that should have fixed any issues with the trucks failed miserably. Whilst I would still happily recommend the boat builder that built the trucks, I wouldnt recommend the company that made the bearings. I have subtly named them in the blog, I wont embarrass them further by naming them more overtly but if you are thinking of having a plastic bearing made on the Central Coast of NSW, perhaps shoot me an email for advise on who not to use.

transom truck in its tracks 1

In the end I have a more robust system, so I cant complain about that. Next job is to figure out the auto and manual lifting/lowering mechanism. I plan on buying a couple of cheap 12v 4WD winches to raise and lower the outboards and a manual backup pulley and rope (and cleat) should the electric winches fail in some way (either jam, stop working or the entire electrics are down). I will glass a ply shelf to the outboard side of each track system and a central turn block above the centre of the outboard tracks that both the electric and manual system can work off. Then I start on the last job in the wells, the copper pipe halyard leads. Then a final white coat and the steps can finally go in, about 5 months later than I thought I could get them in.

But that’s not what I called you here to tell you. Exiting new development in the next post. A must read.

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